package com.jikexueyuan.game2048;

import android.content.Context;
import android.content.DialogInterface;
import android.graphics.Point;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.GridLayout;

import androidx.appcompat.app.AlertDialog;

import java.util.ArrayList;
import java.util.List;

public class GameView extends GridLayout {
    public GameView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        initGameView();
    }

    public GameView(Context context) {
        super(context);
        initGameView();
    }

    public GameView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initGameView();
    }

    private void initGameView(){
        setColumnCount(4);
        setBackgroundColor(0xffdabaab);
        setOnTouchListener(new View.OnTouchListener() {
            private float startX,startY,offsetX,offsetY;
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                switch (event.getAction()) {
                    case MotionEvent.ACTION_DOWN:
                        startX = event.getX();
                        startY = event.getY();
                        break;
                    case MotionEvent.ACTION_UP:
                        offsetX = event.getX()-startX;
                        offsetY = event.getY()-startY;
                        if (Math.abs(offsetX)>Math.abs(offsetY)) {
                            if (offsetX<-5) {
                                swipeLeft();
                            }else if (offsetX>5) {
                                swipeRight();
                            }
                        }else{
                            if (offsetY<-5) {
                                swipeUp();
                            }else if (offsetY>5) {
                                swipeDown();
                            }
                        }
                        break;
                }
                return true;
            }
        });
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        int cardWidth = (Math.min(w, h)-10)/4;
        addCards(cardWidth,cardWidth);
        startGame();
    }

    private void addCards(int cardWidth,int cardHeight){
        Card c;
        for (int y = 0; y < 4; y++) {
            for (int x = 0; x < 4; x++) {
                c = new Card(getContext());
                c.setNum(0);
                addView(c, cardWidth, cardHeight);
                cardsMap[x][y] = c;
            }
        }
    }

    private void startGame(){
        MainActivity.getMainActivity().clearScore();
        for (int y = 0; y < 4; y++) {
            for (int x = 0; x < 4; x++) {
                cardsMap[x][y].setNum(0);
            }
        }
        addRandomNum();
        addRandomNum();
    }

    private void addRandomNum(){
        emptyPoints.clear();
        for (int y = 0; y < 4; y++) {
            for (int x = 0; x < 4; x++) {
                if (cardsMap[x][y].getNum()<=0) {
                    emptyPoints.add(new Point(x, y));
                }
            }
        }
        Point p = emptyPoints.remove((int)(Math.random()*emptyPoints.size()));
        cardsMap[p.x][p.y].setNum(Math.random()>0.1?2:4);
    }


    private void swipeLeft(){
        boolean merge = false;
        for (int y = 0; y < 4; y++) {
            for (int x = 0; x < 4; x++) {
                for (int x1 = x+1; x1 < 4; x1++) {
                    if (cardsMap[x1][y].getNum()>0) {
                        if (cardsMap[x][y].getNum()<=0) {
                            cardsMap[x][y].setNum(cardsMap[x1][y].getNum());
                            cardsMap[x1][y].setNum(0);
                            x--;
                            merge = true;
                        }else if (cardsMap[x][y].equals(cardsMap[x1][y])) {
                            cardsMap[x][y].setNum(cardsMap[x][y].getNum()*2);
                            cardsMap[x1][y].setNum(0);
                            MainActivity.getMainActivity().addScore(cardsMap[x][y].getNum());
                            merge = true;
                        }
                        break;
                    }
                }
            }
        }
        if (merge) {
            addRandomNum();
            checkComplete();
        }
    }
    private void swipeRight(){
        boolean merge = false;
        for (int y = 0; y < 4; y++) {
            for (int x = 3; x >=0; x--) {
                for (int x1 = x-1; x1 >=0; x1--) {
                    if (cardsMap[x1][y].getNum()>0) {
                        if (cardsMap[x][y].getNum()<=0) {
                            cardsMap[x][y].setNum(cardsMap[x1][y].getNum());
                            cardsMap[x1][y].setNum(0);
                            x++;
                            merge = true;
                        }else if (cardsMap[x][y].equals(cardsMap[x1][y])) {
                            cardsMap[x][y].setNum(cardsMap[x][y].getNum()*2);
                            cardsMap[x1][y].setNum(0);
                            MainActivity.getMainActivity().addScore(cardsMap[x][y].getNum());
                            merge = true;
                        }
                        break;
                    }
                }
            }
        }
        if (merge) {
            addRandomNum();
            checkComplete();
        }
    }
    private void swipeUp(){
        boolean merge = false;
        for (int x = 0; x < 4; x++) {
            for (int y = 0; y < 4; y++) {
                for (int y1 = y+1; y1 < 4; y1++) {
                    if (cardsMap[x][y1].getNum()>0) {
                        if (cardsMap[x][y].getNum()<=0) {
                            cardsMap[x][y].setNum(cardsMap[x][y1].getNum());
                            cardsMap[x][y1].setNum(0);
                            y--;
                            merge = true;
                        }else if (cardsMap[x][y].equals(cardsMap[x][y1])) {
                            cardsMap[x][y].setNum(cardsMap[x][y].getNum()*2);
                            cardsMap[x][y1].setNum(0);
                            MainActivity.getMainActivity().addScore(cardsMap[x][y].getNum());
                            merge = true;
                        }
                        break;
                    }
                }
            }
        }
        if (merge) {
            addRandomNum();
            checkComplete();
        }
    }
    private void swipeDown(){
        boolean merge = false;
        for (int x = 0; x < 4; x++) {
            for (int y = 3; y >=0; y--) {
                for (int y1 = y-1; y1 >=0; y1--) {
                    if (cardsMap[x][y1].getNum()>0) {
                        if (cardsMap[x][y].getNum()<=0) {
                            cardsMap[x][y].setNum(cardsMap[x][y1].getNum());
                            cardsMap[x][y1].setNum(0);
                            y++;
                            merge = true;
                        }else if (cardsMap[x][y].equals(cardsMap[x][y1])) {
                            cardsMap[x][y].setNum(cardsMap[x][y].getNum()*2);
                            cardsMap[x][y1].setNum(0);
                            MainActivity.getMainActivity().addScore(cardsMap[x][y].getNum());
                            merge = true;
                        }
                        break;
                    }
                }
            }
        }

        if (merge) {
            addRandomNum();
            checkComplete();
        }
    }

    private void checkComplete(){

        boolean complete = true;

        ALL:
        for (int y = 0; y < 4; y++) {
            for (int x = 0; x < 4; x++) {
                if (cardsMap[x][y].getNum()==0||
                        (x>0&&cardsMap[x][y].equals(cardsMap[x-1][y]))||
                        (x<3&&cardsMap[x][y].equals(cardsMap[x+1][y]))||
                        (y>0&&cardsMap[x][y].equals(cardsMap[x][y-1]))||
                        (y<3&&cardsMap[x][y].equals(cardsMap[x][y+1]))) {

                    complete = false;
                    break ALL;
                }
            }
        }

        if (complete) {
            new AlertDialog.Builder(getContext()).setTitle("你好").setMessage("游戏结束").setPositiveButton("重来", new DialogInterface.OnClickListener() {

                @Override
                public void onClick(DialogInterface dialog, int which) {
                    startGame();
                }
            }).show();
        }

    }

    private Card[][] cardsMap = new Card[4][4];
    private List<Point> emptyPoints = new ArrayList<Point>();
}
